Matrix metalloproteinase 2 governs extracellular matrix remodeling during ovarian development in a viviparous teleost Sebastes schlegelii (Hilgendorf, 1880).

BACKGROUND: Sebastes schlegelii (Hilgendorf, 1880), a viviparous fish with annual ovarian remodeling, shows marked activation of Extracellular Matrix (ECM)-receptor interaction signaling post-mating. However, the evolutionary conservation and functional significance of a key ECM remodeler-Matrix metalloproteinase 2 (MMP2) in this unique reproductive system are poorly understood. RESULTS: In this study, we identified the core members of the MMP family from the S. schlegelii genome and investigated their expression patterns and localization in ovarian tissues. The results demonstrated that the gelatinase gene mmp2 (Ssc_10020200) displayed high expression levels in the mated ovaries, with its expression being predominantly located in the ovarian follicular cell layers and follicular placenta and embryos. Both in vitro and in vivo experiments revealed that MMP2 knockdown during the vitellogenic and gestation stages led to significant ovarian developmental abnormalities. Furthermore, MMP2 knockdown induced a reduction in ECM components such as COL4Α1, LAMB1, and FN1B, accompanied by enhanced apoptotic signaling. CONCLUSIONS: This study suggests that MMP2 plays a vital role in modulating ECM remodeling and maintaining ovarian tissue homeostasis, further ensuring normal ovarian development and healthy reproductive processes. Our findings elucidate a critical function for MMP2 in ovarian development of viviparous teleost, and may inspire further strategies to enhance fish reproductive health and aquaculture outcomes.